Tuesday, 11 September 2012

More fun with understanding the pi's GPIO using python, and the breadboard (solderless circuit board for prototyping electronics) kit from SK Pang:
  • Connect GPIO18 (pin position 12 - yellow wire in the image) to breadboard connected to LED's positive anode (longer leg). The LED's cathode is connected to a resistor, which is connected to ground on the breadboard. The red wire connects breadboard ground with the GPIO header pin 6, which is ground.

  • Install python RPi.GPIO via: sudo apt-get install python3-rpi.gpio
import time
import RPi.GPIO as GPIO

GPIO.setmode(GPIO.BCM) # use formal names, not pin positions
GPIO.setup(18, GPIO.OUT) # set GPIO18 to be output rather than input

for TIMES in range(10):
     GPIO.output(18, True) # enable GPIO18
     GPIO.output(18, False) # disable GPIO18
  • run script (as root: GPIO is privileged) sudo python3 led.py
  • the LED will flash on for a second and off for a second in a loop 10 times.
Takeaway: GPIO allows programmatic control of the input/output pins on the Pi. There are python, C, Java and assembler (any more?) options for controlling GPIO on the Pi.


  1. Cool post, helped me. One thing though you need to change:
    import RPi.GIO as GPIO
    import RPi.GPIO as GPIO

    Thanks dude :)